Ship&#39;s log.



No. 677,020. Patented June 25, 190i.

J. C. COUMBS & A. N. MCGRAY. SHIPS LOG.

(Application filed Sept. 6, 1900.)

(No Model.)

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iJNiTnn STATES PATENT Genres,

JOHN COLBY COOMBS AND ARTHUR NEHEMIAI-I MOGRAY, OF BOSTON,MASSACHUSETTS.

SHIPS LOG.

SPECIFICATION forming part Of Letters Patent N0. 677,020, dated June 25,1901.

Application filed September 6, 1900. Serial No. 29,188. (No model.)

To all whom, it Worry concern:

Be it known that we, J OHN COLBY CooMBs and ARTHUR NEHEMIAH MoGRAY,citizens of the United States, residing at Boston, in the county ofSuffolk, Commonwealth of Massachusetts, have invented certain new anduseful Improvements in Ships Logs, of which the following is aspecification.

The object of our invention is to prevent water entering into theinterior of the log in the direction of the rotator-shaft and to forceout of the interior ofthe log any Water that might be in or entertherein, which we attain in the following manner:

Figure 1 is a log with ourinvention. Fig. 2 is a detail section of Fig.1, showing our invention. Fig. 3 is also a detail section of Fig. 1.

A represents the log-casing, and a the logsteadying vane.

B denotes the rotator, which is fixedly secured to the log-shaft,(represented by the letter C.) The rotator-shaft or log-shaft isprovided with the spiral channels or grooves 0, one or more of which maybe cut into the shaft at any desired angle with its axis and may extendhalf-way through the log-casing in the back end port-ion of the log, andlike ways or grooves may be cut in like angles with the axis as theshaft emerges from the log-casing into the water and may extend equallyhalf-way into the casing, but are not continuous or ever in openconnection with each other. In the middle portion of the easing in whichthe groove parts of the shaft revolve there is a corresponding way orgroove, (represented by the letter c,) which overlaps the respectiveends of the grooves in the shaft at certain points in its revolu tion.These grooves respectively in the shaft and the casing are so cut inrelation to each other that in no position can they be in suchcontinuous connection as to permit water to flow in or out of thelog-casing, and the operation designed is that as the shaft revolves thewater in the log-casing will be taken up by the grooves on the shaft incontact therewith and flow into the grooves in the log-casing, fromwhich it will again in the progress of the revolution of the shaft flowinto the grooves in the shaft and flow as the shaft revolves into thesea, thereby withdrawing or expelling all water from the interior of thelog-casing.

Having described our invention, we claim- In a ships 10g, means forpreventing Water entering into the interior of, and expelling water fromthe interior of the log-casing, consisting of a spiral channel providedin the end of the log-casing, and spiral channels provided on therotator-shaft adapted to alternatively make a communication from theinterior of the log to the exterior thereof, and break saidcommunication in each successive revolution of the rotator-shaft, asdescribed. In testimony whereof we have hereunto set our hands this 6thday of July, A. D. 1900.

JOHN COLBY OOOMBS. ARTHUR NEHEMIAI-I MCGRAY. lVitnesses:

F. C. OHAMBERLIN, CHARLES H. HANSON.

